European Commission proposes Stage III emission standards for nonroad diesel engines

14 January 2003

The European Commission has proposed Stage III legislation to control emissions from diesel engines that are used in nonroad machinery in the European Union (EU). The proposal aims to reduce the impact of diesel emissions on the formation of ozone and the negative health effects of particles. The proposed legislation will also help support the promotion of inland waterway shipping and railways as environmentally friendly modes of transport. The proposed Stage III B PM limits have been designed to ensure that all future diesel engines are equipped with particulate filters or equivalent technologies. The legislation has been developed in close co-operation with the US Environmental Protection Agency (EPA) to achieve worldwide harmonization of emission limits.

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Current emission legislation (Directive 97/68/EC) contains two stages for introducing limit values. The Stage I limits have been already implemented. Stage II will be fully implemented by the end of 2003. The purpose of the proposed Stage III is to reduce emissions of nitrogen oxides and particulates and thereby improve the future air quality situation. If no further measures were implemented the emissions of those pollutants from nonroad mobile machinery would in about 15 years be as high as from road transport.

Stage III will be implemented in two phases. The first phase (Stage III A) only covers gaseous pollutants. This part is equivalent to the corresponding legislation in the USA and can therefore be implemented with a very short lead-time. Depending on the size of the engine the limit values will enter into force between 31 December 2005 and 31 December 2007. Compared with the Stage II limits, engines meeting the Stage III A limit values will emit about 30% less oxides of nitrogen.

The second phase (Stage III B) will cover particulate emissions and will enter into force between 31 December 2010 and 31 December 2011. To meet these limit values it is anticipated that the engines will be equipped with particulate filters. Compared to Stage II engines the emissions of particles will be about 90% lower. The use of particulate filters also requires the use of low sulfur fuel and the Commission said it will present the necessary legislation in this field. Furthermore, to represent emissions during real conditions, the particulate emissions will be measured with a newly developed transient test procedure, the Nonroad Transient Cycle (NRTC). Existing nonroad standards in the EU and in the USA are based on the steady state ISO 8178-4 C1 8-mode cycle.

The proposed legislation (similar to the current standards) is globally aligned, meaning that a manufacturer can offer the same engine concept worldwide. The Commission said it developed the proposal in close co-operation with authorities and industry in Europe, the USA and Japan. The US EPA is expected to present a corresponding proposal for legislation within a few of months.

Unlike in the current legislation, engines used in inland waterway vessels are also included. Since engines on ships were excluded from the Stage I/II standards, the limit values proposed for inland waterway vessels are not as strict as for the other applications which have already been covered by two stages of limit values. The Commission said that railroad locomotives emission standards should be ultimately also harmonized with US regulations, but the proposal does not cover locomotive emission testing issues.

A part of the proposal is a technical review scheduled to take place in 2006. This review will identify any necessary changes needed to achieve as close worldwide alignment as possible. It will also be possible to benefit from technical development, which might result in further tightening of limit values for gaseous pollutants but also to make necessary exemptions from Stage III B limits if unexpected technical difficulties arise. This technical review will also make it possible to introduce stricter limit values for engines in inland waterway vessels if deemed appropriate.

The proposed emission limits are listed in the following tables.

Source: European Commission